Many of polycyclic aromatic hydrocarbons (PAHs) have been identified as the highly toxic pollutants. The PAHs' contamination has made surrounding people and animals suffer from the exposure by air, water and soil. Remediation of the Superfund sites requires on-site discrimination, detection and monitoring of PAHs. Detection of trace levels of PAHs are usually performed by legacy laboratory analytical techniques including GC/MS or GC/FID, and HPLC with fluorescence or UV-Vis detection, which are bulky, expensive, time-consuming, or often requiring complex separation and preconcentration steps. Based on our successful commercialization of portable Raman instruments and our experience in ultrasensitive chemical detection based on surface-enhanced Raman spectroscopy (SERS), Agiltron proposes to develop a robust portable microfluidic SERS detector and the methodology for field analysis of PAHs in liquid media at Superfund sites. In Phase I, we will fabricate and optimizes PAHs SERS sensor chips by chemically modifying our proprietary high-performance AgNF SERS chips with various partition layers; SERS spectra of all the 16 EPA priority PAHs in water and methanol will be measured to build a library of characteristic SERS bands distinguishable among them; individual and simultaneous detection of 3 selected PAHs with a detection limit performance goal of 0.1 g/L (ppb) will be demonstrated; and an optimized SERS chip will be integrated into a flow cell and tested on our PinPointer(tm) Raman spectrometer; In Phase II, we will refine and optimize this detection technology and extend it to study the effects of various factors and elimination of interference. Microfluidic SERS cartridges will be fabricated and a field-portable Raman prototype will be built for field tests at Superfund sites. The proposed SERS detector provides a unique solution to distinguish and quantify trace levels of PAHs under ambient conditions with no need for extra preconcentration and separation. It is ultrasensitive, extremely simple, and highly reliable, and allows relatively unskilled personnel to accomplish on site PAHs testing, affording a cost-effective monitoring tool for assessment, remediation and management of Superfund sites and other contaminated sources. The broad markets for this proposed device include, but are not limited to, US EPA contractors, testing and research laboratories, state and municipal water authorities, and environmental remediation companies.